Gravity liquid filtration apparatus

Abstract

A gravity liquid filtration apparatus includes a housing with a pool forming assembly mounted between a pair of side walls in the housing. The pool forming assembly includes a central shaft with a pair of spaced-apart discs rotatably mounted on the shaft between the side walls. A filter media is supported on an endless loop carrier belt, and pressed against the peripheral edges of the containment discs along bottom arcs thereof to form a generally semi-cylindrical shaped pool. A liquid inflow assembly on the housing includes a delivery head with a nozzle portion having an elongated mouth aimed downwardly to discharge liquid onto a downwardly sloped portion of the filter media. A box is formed in the delivery head above the nozzle of a size to permit large objects such as pens and pencils to fall flat and be discharged through the mouth of the nozzle. Each disc in the pool forming assembly includes a groove along the peripheral edge with a resilient seal ring journaled in the groove to provide a seal against the filter media and carrier belt. Each disc includes a plurality of overflow apertures formed therein and located along a circle centered on the shaft. Pusher bar assemblies are mounted between the discs for pushing caked particulate off of the upper surface of the belt. A tensioner assembly supports each end of the shaft in the side walls, and includes a spring biased set collar which receives one end of the shaft to permit vertical movement of the shaft, but prevents horizontal and rotational movement of the shaft. The set collar is spring biased to maintain a biasing force of the discs against the filter media.

We claim: 
     
       1. A gravity liquid filtration apparatus, comprising: a housing having forward and rearward ends, opposing vertical side walls, and upper and lower ends;   a pool forming assembly operably mounted between the side walls, including: a central shaft extending generally horizontally between the side walls;   a pair of spaced-apart containment discs rotatably mounted on said shaft, said containment discs each having a peripheral edge and a plurality of overflow apertures formed therethrough and located generally along a circle centered on the shaft;     an elongated filter medium for filtering particulate from liquid passing through the filter medium belt;   an elongated filter medium carrier belt for supporting said filter medium belt and for pressing it against the peripheral edges of the containment discs along corresponding bottom arcs thereof;   said carrier belt formed of an endless web and a plurality of rollers which support the endless belt such that a run thereof is pressed towards the bottom arcs of the containment discs;   drive means for driving the carrier belt; and   a liquid inflow assembly on said housing including: a delivery head having a nozzle portion extending between and radially inwardly of the peripheries of the discs;   said nozzle portion having an elongated mouth which is aimed downwardly so as to discharge liquid to be filtered onto a downwardly sloped portion of the filter medium supported on the carrier belt.     
     
     
       2. The apparatus of claim 1, wherein each containment disc includes a groove formed along the entire peripheral edge, and further including a resilient seal ring journaled along the extent of the groove and projecting radially therefrom in sealed engagement along the bottom arc against the filter medium and carrier belt. 
     
     
       3. The apparatus of claim 2, wherein said nozzle portion includes an upper chamber having a generally horizontal bottom wall, the upper chamber connected to the mouth by an arcuate chamber, wherein said inflow assembly includes a vertically oriented inlet tube through which inflow liquid is discharged into the delivery head. 
     
     
       4. The apparatus of claim 3, wherein said delivery head includes a box, and said box has a height of at least about six inches. 
     
     
       5. The apparatus of claim 4, further comprising a pusher bar assembly mounted between the discs, for pushing caked particulate formed on an upper surface of the filter belt within the pool forming assembly, the pusher bar assembly including: a spacer bar extending between the discs, spaced radially inwardly of the peripheral edges, for movement with the rotation of the discs;   a pair of spaced-apart, parallel support arms pivotally mounted at first ends on the spacer bar; and   a shovel bar mounted on second ends of the support arms and oriented parallel to the spacer bar, which can contact a run of the filter medium belt on the carrier belt along the bottom arcs of the discs.   
     
     
       6. The apparatus of claim 5, wherein the shovel bar is rectangular in cross-section. 
     
     
       7. The apparatus of claim 6, wherein the pusher bar assembly further includes: a lift pin mounted on each end of the spacer bar proximal each support arm, for rotation with the spacer bar and extending radially outwardly therefrom; and   a support pin mounted on each support arm oriented parallel to the spacer bar and projecting from each support arm to an extent which will place it in contact with a lift pin as the support arms pivot on the spacer bar.   
     
     
       8. The apparatus of claim 7, further comprising a tensioner assembly connected between each end of the shaft and the associated side wall, for biasing the shaft vertically downwardly while preventing horizontal, longitudinal, and rotational movement of the shaft. 
     
     
       9. The apparatus of claim 8, wherein each said tensioner assembly includes: a block fastened to the side wall, having a horizontal opening formed therethrough through which one end of the shaft projects;   a set collar positioned within the block opening and secured to the end of the shaft with a set screw;   a rod mounted on a lower portion of the set collar and projecting through a vertically oriented guide aperture in the block below the block opening;   a stop member on a lower end of the rod spaced below the block; and   biasing means between the stop member and block for biasing the stop member, rod, set collar and shaft vertically downwardly.   
     
     
       10. The apparatus of claim 9, wherein the rod is threaded, and wherein the stop member is threaded on the rod, for selective adjustment therealong. 
     
     
       11. The apparatus of claim 10, wherein the set screw is aligned coaxially with the rod, and journaled through a vertical aperture in the block above the block opening. 
     
     
       12. The apparatus of claim 1, wherein said nozzle portion includes an upper chamber having a generally horizontal bottom wall, the upper chamber connected to the mouth by an arcuate chamber, wherein said inflow assembly includes a vertically oriented inlet tube through which inflow liquid is discharged into the delivery head. 
     
     
       13. The apparatus of claim 1, further comprising a pusher bar assembly mounted between the discs, for pushing caked particulate formed on an upper surface of the filter belt within the pool forming assembly, the pusher bar assembly including: a spacer bar extending between the discs, spaced radially inwardly of the peripheral edges, for movement with the rotation of the discs;   a pair of spaced-apart, parallel support arms pivotally mounted at first ends on the spacer bar; and   a shovel bar mounted on second ends of the support arms and oriented parallel to the spacer bar, which can contact a run of the filter medium on the carrier belt along the bottom arcs of the discs.   
     
     
       14. The apparatus of claim 13, wherein the pusher bar assembly further includes: a lift pin mounted on each end of the spacer bar proximal each support arm, for rotation with the spacer bar and extending radially outwardly therefrom; and   a support pin mounted on each support arm oriented parallel to the spacer bar and projecting from each support arm to an extent which will place it in contact with a lift pin as the support arms pivot on the spacer bar.   
     
     
       15. The apparatus of claim 1, further comprising a tensioner assembly connected between each end of the shaft and the associated side wall, for biasing the shaft vertically downwardly while preventing horizontal, longitudinal, and rotational movement of the shaft. 
     
     
       16. The apparatus of claim 15, wherein each said tensioner assembly includes: a block fastened to the side wall, having a horizontal opening formed therethrough through which one end of the shaft projects;   a set collar positioned within the block opening and secured to the end of the shaft with a set screw;   a rod mounted on a lower portion of the set collar and projecting through a vertically oriented guide aperture in the block below the block opening;   a stop member on a lower end of the rod spaced below the block; and   biasing means between the stop member and block for biasing the stop member, rod, set collar and shaft vertically downwardly.   
     
     
       17. A gravity liquid filtration apparatus, comprising: a housing having forward and rearward ends, opposing vertical side walls, and upper and lower ends;   a pool forming assembly operably mounted between the side walls, including: a central shaft extending generally horizontally between the side walls;   a pair of spaced-apart containment discs rotatably mounted on said shaft, said containment discs each having a peripheral edge and a plurality of overflow apertures formed therethrough and located generally along a circle centered on the shaft;     an elongated filter medium for filtering particulate from liquid passing through the filter medium;   an elongated filter medium carrier belt for supporting said filter medium and for pressing it against the peripheral edges of the containment discs along corresponding bottom arcs thereof;   said carrier belt formed of an endless belt and a plurality of rollers which support the endless belt such that a run thereof is pressed towards the bottom arcs of the containment discs;   drive means for driving the carrier belt; and   a liquid inflow assembly on said housing including: a delivery head having a nozzle portion extending between and radially inwardly of the peripheries of the discs;   said nozzle portion having an elongated mouth which is aimed downwardly so as to discharge liquid to be filtered onto a downwardly sloped portion of the filter medium supported on the carrier belt;   said nozzle portion including an upper chamber having a generally horizontal bottom wall, the upper chamber connected to the mouth by an arcuate chamber;   a vertically oriented inlet tube through which inflow liquid is discharged into the delivery head;   said delivery head including a box having an open upper end communicating with the inlet tube and an open lower end communicating with the upper chamber of the nozzle portion, the box having a transverse width greater than a diameter of the inlet tube and extending towards the side walls, and a height of at least about six inches.     
     
     
       18. A gravity liquid filtration apparatus, comprising: a housing having forward and rearward ends, opposing vertical side walls, and upper and lower ends;   a pool forming assembly operably mounted between the side walls, including: a central shaft extending generally horizontally between the side walls;   a pair of spaced-apart containment discs rotatably mounted on said shaft, said containment discs each having a peripheral edge and a plurality of overflow apertures formed therethrough and located generally along a circle centered on the shaft;     an elongated filter medium for filtering particulate from liquid passing through the filter medium;   an elongated filter medium carrier belt for supporting said filter medium and for pressing it against the peripheral edges of the containment discs along corresponding bottom arcs thereof;   said carrier belt formed of an endless belt and a plurality of rollers which support the endless belt such that a run thereof is pressed towards the bottom arcs of the containment discs;   drive means for driving the carrier belt; and   a liquid inflow assembly on said housing including: a delivery head having a nozzle portion extending between and radially inwardly of the peripheries of the discs;   said nozzle portion having an elongated mouth which is aimed downwardly so as to discharge liquid to be filtered onto a downwardly sloped portion of the filter media supported on the carrier belt; and     a pusher bar assembly mounted between the discs, including: a spacer bar extending between the discs, spaced radially inwardly of the peripheral edges, for movement with the rotation of the discs;   a pair of spaced-apart, parallel support arms pivotally mounted at first ends on the spacer bar; and   a shovel bar mounted on second ends of the support arms and oriented parallel to the spacer bar, which can contact a run of the filter medium on the carrier belt along the bottom arcs of the discs.     
     
     
       19. The apparatus of claim 18, wherein the pusher bar assembly further includes: a lift pin mounted on each end of the spacer bar proximal each support arm, for rotation with the spacer bar and extending radially outwardly therefrom; and   a support pin mounted on each support arm oriented parallel to the spacer bar and projecting from each support arm to an extent which will place it in contact with a lift pin as the support arms pivot on the spacer bar.   
     
     
       20. A gravity liquid filtration apparatus, comprising: a housing having forward and rearward ends, opposing vertical side walls, and upper and lower ends;   a pool forming assembly operably mounted between the side walls, including: a central shaft extending generally horizontally between the side walls;   a pair of spaced-apart containment discs rotatably mounted on said shaft, said containment discs each having a peripheral edge and a plurality of overflow apertures formed therethrough and located generally along a circle centered on the shaft;     an elongated filter medium for filtering particulate from liquid passing through the filter medium;   an elongated filter medium carrier belt for supporting said filter medium and for pressing it against the peripheral edges of the containment discs along corresponding bottom arcs thereof;   said carrier belt formed of an endless belt and a plurality of rollers which support the endless belt such that a run thereof is pressed towards the bottom arcs of the containment discs;   drive means for driving the carrier belt; and   a liquid inflow assembly on said housing including: a delivery head having a nozzle portion extending between and radially inwardly of the peripheries of the discs;   said nozzle portion having an elongated mouth which is aimed downwardly so as to discharge liquid to be filtered onto a downwardly sloped portion of the filter media supported on the carrier belt; and   a tensioner assembly connected between each end of the shaft and the associated side wall, for biasing the shaft vertically downwardly while preventing horizontal, longitudinal, and rotational movement of the shaft.     
     
     
       21. The apparatus of claim 20, wherein each said tensioner assembly includes: a block fastened to the side wall, having a horizontal opening formed therethrough through which one end of the shaft projects;   a set collar positioned within the block opening and secured to the end of the shaft with a set screw;   a rod mounted on a lower portion of the set collar and projecting through a vertically oriented guide aperture in the block below the block opening;   a stop member on a lower end of the rod spaced below the block; and   biasing means between the stop member and block for biasing the stop member, rod, set collar and shaft vertically downwardly.   
     
     
       22. The apparatus of claim 21, wherein the rod is threaded, and wherein the stop member is threaded on the rod, for selective adjustment therealong. 
     
     
       23. The apparatus of claim 22, wherein the set screw is aligned coaxially with the rod, and journaled through a vertical aperture in the block above the block opening.